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Common Science 



FIG. 162. Filling a balloon with hydrogen. 



parts of water. Find the bottle marked "HC1, dilute 1-3," 

 in which the acid is already diluted. Before you open the 

 bottle, get some solution of soda, and keep it near you ; if 

 in this experiment or any other you spatter acid on your 

 hands or face or clothes, wash it off immediately with soda 

 solution. Remember this. Ammonia will do as well as the 

 soda solution to wash off the acid, but be careful not to get 

 it into your eyes. 



Pour the hydrochloric acid (HC1) on the zinc shavings in 

 the bottom of the flask, until the acid stands about an inch 

 deep. Then quickly put the rubber stopper with its attach- 

 ments into the flask, so that the gas that bubbles up will 

 blow up the balloon. 



